1. Field of the Invention
The present invention relates to an illumination apparatus, a pattern irradiation device, and a system.
2. Description of the Related Art
Conventionally, systems are known that use robots to handle objects (works) loaded on a tray, convey the objects to a device in the next process, and assemble products by using the objects. In such systems, a three-dimensional measuring device is used to measure the distance to an object on the tray, and the object is handled by recognizing the position and the posture thereof based on the measurement results. In such systems, a pattern irradiation device irradiates the objects on the tray with light in a predetermined pattern, thereby improving the accuracy of distance measurement performed by the three-dimensional measuring device (refer to Japanese Laid-open Patent Publication No. 2013-222056 and Japanese Laid-open Patent Publication No. 2013-257162, for example). The pattern irradiation device can be achieved by a configuration similar to that of a projection apparatus (projector) using a digital mirror device (DMD), a liquid crystal panel, or the like. Other conventional examples are described in Japanese Laid-open Patent Publication No. 2014-010181 and Japanese Laid-open Patent Publication No. 2013-076902.
Because the optical system of the projector using the DMD or the liquid crystal panel includes a relay optical system and an optical system used to combine respective colors, it has a number of components. Accordingly, the pattern irradiation device having a configuration similar to that of the projector is large in size and is expensive.
In view of the above, there is a need to provide an illumination apparatus, a pattern irradiation device, and a system that can obtain high optical output as well as reduce the size and the cost.